EM78P468LAQ EMC [ELAN Microelectronics Corp], EM78P468LAQ Datasheet - Page 19

• Manufacturer Part Number: EM78P468LAQ
• Description: 8-BIT Microcontroller
• Manufacturer: EMC [ELAN Microelectronics Corp]

Product Specification (V1.0) 03.15.2006
(This specification is subject to change without further notice)
4.1.10
4.1.11
Bit 7 (BS): LCD bias select bit,
Bit 6 ~ 5 (DS1 ~ DS0): LCD duty select
Bit 4 (LCDEN) : LCD enable bit
Bit 3: Not used
Bit 2 (LCDTYPE) : LCD drive waveform type select bit
Bit 1 ~ 0(LCDF1 ~ LCDF0): LCD frame frequency control bits
Fs: sub-oscillator frequency
Bit 7 ~ 5: Not used, fixed to “0”
LCDF1
Bit 7
Bit 7
BS
0
0
1
1
0
DS1
BS = “0”: 1/2 bias
BS = “1”: 1/3 bias
LCDEN = “0” : LCD circuit disable. all common/segment outputs are set to ground
(GND) level
LCDEN = “1” : LCD circuit enable.
LCDTYPE = “0” : A type waveform
LCDTYPE = “1” : B type waveform
(Address: 09h)
(Address: 0Ah)
0
0
1
R9/LCDCR (LCD Control Register)
RA/LCD_ADDR (LCD Address)
LCDF0
Bit 6
DS1
Bit 6
0
0
1
0
1
DS0
X
0
1
Bit 5
DS0
Bit 5
Fs/(256*2)=64.0
Fs/(280*2)=58.5
Fs/(304*2)=53.9
Fs/(232*2)=70.6
0
1/2 duty
LCD frame frequency (e.g. Fs=32.768KHz)
LCDEN
LCD_A4 LCD_A3 LCD_A2 LCD_A1 LCD_A0
Bit 4
Bit 4
LCD duty
1/2 duty
1/3 duty
1/4 duty
Bit 3
--
Bit 3
Fs/(172*3)=63.5
Fs/(188*3)=58.0
Fs/(204*3)=53.5
Fs/(156*3)=70.0
1/3 duty
LCDTYPE LCDF1
Bit 2
Bit 2
8-BIT Microcontroller
Bit 1
Fs/(128*4) =64.0
Fs/(140*4) =58.5
Fs/(152*4) =53.9
Fs/(116*4) =70.6
Bit 1
1/4 duty
EM78P468L
LCDF0
Bit 0
Bit 0
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